Polysulfide sealing putties and compounds



Patented Mu. 29,1949

Frederic M. Cara-o, l'aaadena, aaalgnor to Lockheed AircraftCorporation. Burbank,

No Drawing. Application October 22, 1945,

Calif.

Serial No. mass 15 mm. (01. zoo-29.2)

This invention relates to coating and sealing materials, and relatesmore particularly to such materials compounded from aqueous dispersionsof polymeric organic polysulfides. This application is a continuation inpart of my application, Serial No. 563,323, filed November 13, 1944, andnow abandoned, and entitled Sealing compounds. J

The composition of matter provided by'this invention has a wideapplication and is useful in practically any situation where adherentcoatings or masses of rubber-like sealing materials are required. Theinvention finds one important application in vehicle fuel tanks subjectto vibration and flexure. Tanks formed integral with the wings,fuselages, etc., of aircraft are examples of such containers or tanks.The sealing of the seams, rivets, and the like, of these tanks haspresented a difllcult problem. Various special sealing materials havebeen proposed, but for the most part, have proven unsatisfactory due totheir inability to maintain full adhesion and adequate elasticity underthe prevailing conditions of usage. The elasticity and adherence must bemaintained in the presence of fuel, oil, water, etc., throughout asubstantial range of temperatures, and the sealing material must be suchthat it does not develop pin holes, sag because of excessive softness,or crack by reason of becoming excessively hard.

Attempts have been made to employ aqueous dispersions of polymericorganic polysulfides as the basic ingredientsfor sealing materials ofthe class under consideration. The principal disadvantage to thepractical utilization of such aqueous dispersions of polymeric organicpolysulfides has been the difficulty in obtaining satisfactory andcontrolled coalescence in order to produce coherent and adherentcoatings of good quality rubber.

It is an important object of this invention to economically andsatisfactorily utilize aqueous dispersions of polymeric organicpolysulfides to obtain coherent and adherent rubber-like coatings andmasses upon the exposure of thematerial to conditions conducive tocoalescence. The invention provides a simple, practical and effectivemeans for producing coherent and adherent coatings, films and massesfrom the aqueous dispersions. The product of the invention has a highdegree of adherence to metals of various kinds, wood, etc., remainsflexible and resilient throughout a wide temperature range, and in thepresence of fuels, oils, water and other fluids, and is therefore wellsuited for the sealing II A still further object of the invention is toproof tanks, containers and enclosures subject to vibration and flexure.

Another object of the invention is to provide a composition of matterobtained from the treatment of aqueous dispersions of polymeric organicpolysulfides, and suitable for use as a coating, sealing and caulkingmaterial, which, when properly packaged, will remain water dispersibleand unchanged for a prolonged storage period. The

material may be immediately applied following preparation, or may bestored indefinitely for sub-' sequent use.

- quent to being removed from storage and, if desired, may be modifiedin character during or subsequent to its processing to have the desiredphysical attributes. The material of the invention may be marketed ordistributed as a singlepackage product adapted for direct application toa variety of surfaces as a putty-like fllleting, caulking and sealingmaterial for the sealing of containers and tanks. When diluted to anappropriate viscosity, the material may be applied by extrusion,spatula, brushing, spraying, sloshing or other methods to yield coherentand a erent sealing coatings of practically any desire thickness. Aftercoalescence the material is no longer dispersible, and is resistant towater and other fluids.

Another object of the invention is to provide highly effectivecoalescing agents for aqueous or non-aqueous dispersions of polymericorganic polysulfides from whichcoherent and adherent coatings and massesmay be obtained. The class of coalescing or coagulating agents of theinvention may also, if desired, be employed to produce coherent massesor sheets of rubber-like material without the necessity of employingacids, this function being distinct from the function of producingsealing putty and coatings.

A further object of the invention is to provide a means or method forproducing, from aqueous dispersions, coalesced blends of polymericorganic polysulfides with other elastomers or synthetic resins.

vide a sealing or coating material of the character referred to thatwillnot corrode alkali-sensitive materials such as aluminum, and that willnot pit, peel or become discontinuous as a result of alkaline reactionwith such materials. The commercially available polymeric organicpolysulfides have a substantial alkaline reaction, the alkalinity beingsuflicient to cause appreciable reaction accompanied by the evolution ofgas when in contact with aluminum and other alkalisensitive materials.The reaction and accompanying gas generation may adversely aflect theadhesion of the sealing material and result in a discontinuous sealingcoating. or mass. In accordance with the invention one or more corrosioninhibitors compatible with the coalescing agent or agents may beincorporated in the material to avoid the reaction and its results.

The sealing and coating material of the invention is capable of widevariation, and the relative proportions of its'components or ingredientsmay be modified materially to adapt it for specific uses. Accordingly,while I have hereinafter described several examples difiering somewhatin proportions and composition, it is to be understood that theinvention is not to be construedas limited to the details set forth.

The composition of matter provided by t invention may be said tocomprise generally one or more polymeric organic polysulfides, one ormore coalescing agents, and where required, a corrosion inhibitor. I

The base or principal ingredient of the sealing and coating material isan aqueous dispersion of an, organic polysulfide polymer resulting fromthe interaction of alkaline polysulfides and chlorinated'organiccompounds or a blend or mixture of two or more such polymers. UnitedStates Letters Patent No. 1,890,191 and No. ,216,044 disclose syntheticlatices of the general character herein referred to. A Thiokol latex isa polysulfide which is a polymer of the unit represents two carbon atomsjoined toand separated by intervening structure. The coalescing aminonitrogen compound containing at least two hydrogen atoms directlyattached to nltrogen. Several objects and advantages of the inventionenumerated herein and other attendant advantages, result from theemployment of one or more of these coalescing agents in processing where"R may be hydrogen or an organic radi-. cle, M" may be an organic amineradicle, am-

monium, or a metallic radicle; and in certain cases, (if the respectivedithiocarbamic acid may exist temporarily) "111 may represent hydrogen,

and where "a and b are simple whole numbers. In most instances, a: b"=1,

Best results are obtained from'the addition product of two moles of aprimary mono-amine ing agents are relatively non-adherent.

agents of the invention have been found to be eflective with, each ofthe three- Thiokol latices now commercially available and designated bytheir manufacturer as Thiokol MF, Thiokol W132 and Thiokol MX. Blends ormixtures of two or more of such latices may be advantageously carbamatesalts in which M, of formula No. 1,.

fldes. Where the terms Thiokol, latex, or latices are herein employed,they are to be understood as meaning an aqueous dispersion of organicpolysulfide polymers resulting from the interaction of alkalinepolysulfides and chlorinatedworganic compounds. As will be laterdescribed, the proportion of the solids in the aqueous dispersion mayvary greatly in difierent applications of the invention.

Furthermore, the latex may be initially supplied for processing eitherin the form of a cake or in a relatively thin dispersion.

The coalescing agents are important ingredi-' ents of the invention. Thecoalescing agents are dlthiocarbamate compounds derived from an for eachmole of carbon disulflde. Here the product may be represented byformulaNo. 2:

substituted dithiocarbamic acids may be employed as coalescing agentsfor the Synthetic latex dispersions, but have been found to be lesseffective than the corresponding amine or ammonium salts. Various typesof amines are more or less effective as coalescing agents for alcoholicdispersions of polymeric organic polysulfides, as well as for aqueousdispersions of the polymeric organic polysulfides, but coatings andsealing:

masses embodying such preparations as coalesc- Tou h coherent sheets ofpolysulflde rubber may be produced by the action of certain amines, andsecondary as well as primary amines may be used for this purpose.However, the performance of these amines alone is definitely interior tothe results obtainable by the useof dithiocarbamic salts derived fromprimary amines.

The use of dithiocarbamate salts in which M.

of formula No. 1, is an alkaline nitrogen-con--- taining radicle.comprising an amine different from that from which the dithiocarbamateradicle is derived, is contemplated by the invention. However, it hasbeen found that entirely satisfactory results are obtainable by the useof dithiocomprises the same amine as employed informing thedithiocarbamate radicle. Blends or mix- .tures of two or more of thedithiocarbamates .may be employed, but it has been found more desirableto use a single dithiocarbamate compound. The use of a free amine inaddition to the dithiocarbamate compound, is also within the scope ofthe invention, but in most instances it is preferred to use thedithiocarbamate salt without an additionalfree amine.

The use of dlthiocarbamate compounds derived from polyamines containingat least one primary amino group (or more generallyv alkaline nitrogencompounds which contain two'or more nitrogen atoms, one of which has twohydrogen atoms directly attached thereto) is also contemplated by theinvention, but I prefer to use the addition product or two moles of aprimary mono amine for each mole of carbondisulflde.

The following examples illustrate compounds that may be used inpreparing the dithiocarbamates, it being understood that the inventionis not to be construed as limited to these particular examples:

Ammonia Mono methylamine Mono ethylamine Mono-n-propylamineMono-iso-propylamine Mono-n-butylamine Mono-iso-butylamineMono-sec-butylamine Mono-amylamine (commercial products, mixed isomers)Mono-n-heptylamine Mono-n-octylamlne Mono-Z-ethyl-hexylamineMono-n-dodecylamine Mono ethanolamine Mono benzylamine Ethylene diamineHexamethylene diamine 1,3-diamino-butane 1,3-diamino-propane Monoallylamine Mono methallyl amine Mono cyclohexyl amine Mono2-methoxyethyl amine Dlthiocarbamate salts prepared from aromatic aminesmay also be employed as coalescing agents. In such instances it is usualto employ amines which have ionization constants in the neighborhood ofor stronger, together with the aromatic amine to insure the formation ofthe dithiocarbamate salt. The following are typical examples ofdithiocarbamate salts prepared from aromatic amines:

Ammonium phenyl dithiocarbamate Ammonium p-tolyl dithiocarbamateAmmonium alpha-naphthyl dithiocarbamate the three Thiokol latices now{commercially available, namely, Thiokol M1", Thiokol WD2,. and

Dlthiocarbamate salts derived from primary mono amines, other thanaromatic amines. are particularly effective as coalescing agents for theaqueous Thiokol dispersions. These include dithiocarbamate salts derivedfrom the following types of amines:

1. Simple or unsubstituted aliphatic amines: (a) Saturated, i. e.,mono-n-butylamine; (b) Unsaturated, i. e., mono allylamine.

2. Substituted aliphatic amines, for example, those containing an etherlinkage, i. e., Z-methoxyethylamine.

3. Alicyclic amines, i. e., cyclohexylamine.

4. Arylalkylamine in which the amino group is Thiokol MK. The coalescingagentsdescribed above may be used to advantage with any blend or mixtureof two or mor of such Thiokol latices, although the properties of theresultant product are dependent to a large degree upon the nature of thepolysulflde latex dispersion from which it is derived and upon thequantity and character of the coalescing agent or agents.

In most embodiments of the invention, relatively small proportions ofthe coalescing agent are used, it being understood that the proportionsof the coalescing agent may be varied within a rather wide range.Ordinarily, from approximately 02% to approximately 10% of the selectedcoalescing agent may be used, but I usually prefer to employ fromapproximately 0.25% to approximately 2% of the coalescing agent. Thepercentages here are in relation to the Thiokol solids of the compounds.

The coalescing agent may be incorporated with the latex dispersion inpractically any selected manner. The following are typical ways ofincorporating the coalescing agent in the dispersion:

(a) The coalescing agent may be incorporated with a concentrated aqueouspolysulflde latex dispersion or cake obtained by allowing the latex tosettle so that the supernatant liquid may be removed, or obtained byfiltering the latex. This concentrated dispersion is relatively solidand is of firm consistency.

(bl The coalescing agent is incorporated in or added to a fluid aqueouslatex dispersion.

(c) A suitable carrier, either aqueous or nonaqueous is utilized tointroduce the coalescing agent into the latex dispersion. Thisfacilitates the uniform distribution of the coalescing agent throughoutthe mixture.

The coalescing agent may be introduced into the synthetic latexdispersion at ordinary room temperatures, or at elevated temperatures asfound most desirable, and may be employed with or without othermaterials to be added to the compound for given purposes. It has beenfound that proper incorporation of the coalescing agent into the latexdispersion is materially facilitated by conducting the mixing operationsubstantially in the absence of air at elevated temperatures rangingfromFahrenheit to 212 Fahrenheit, and by using appropriate mixing technique.

Incorporation of the coalescing agent into a very concentrated aqueouslatex dispersion has been found to be particularly advantageous. Thisyields a superior and highly versatile product and illustrates theremarkable effectiveness of th coalescing agents provided by the presentinvention. The material or polysulflde latex dispersion which, beforetreatment with the coalescing agent is a non-coherent, solid, dough-likemass or cake, is readily converted by a small proportion of thecoalescing agent into a smooth coherent putty-like material whichremains water dispersible, and from which coherent and rubbery coatingsor masses may be readily obtained. This feature of the inventionprovides a simplified and greatly improved method for processing orcompounding a synthetic elastomer. The fact that a substantially solidlatex cake may be treated in a vessel and at elevated temperatures witha relatively small proportion of a coalescing agent without becomingcrumbly and dimcult to handle,

and to yield a smooth coherent water dispersible highly concentrated"putty" which is easy to process, was not known to others prior to thisinvention or contemplated by the prior art known to me. Heretofore, whena solid synthetic latex cake was similarly treated alone or with a priorcoalescing agent, or other substance, itwas impossible to obtain asmooth coherent useful-putty, and in most cases, the resultant productwas dry, crumbly and incoherent.

The above described method of processing a solid cake of the syntheticlatex has distinct advantages. The cake or raw material may be storedand shipped in a concentrated form, and the synthetic rubber may beprocessed 'or compounded in a highly concentrated water dispersible formto produce an extremely versatile product. Furthermore, theeflectiveness of the coalescing agent is apparently increased when theagent is incorporated into the highly concentrated Thiokol cake.

Where the conditions of intended use require,

an altered, compounded or modified product may be prepared byincorporating the coalescing agent of the invention in the latexdispersion in the presence of other ingredients, or during Sub. sequenttreatment of the dispersion. It is important, however, that such addedingredients or subsequent treatment of the dispersion should notadversely aflect the function or purpose of either the coalescing agentor the latex. In'other words, any alteration, modification orcompounding should be limited to materials and procedures compatiblewith the coalescing agent and the polymeric organic polysulflde aqueousdispersion. The following are typical examples of materials which may beadded to, or incorporated in, the sealing and coating material:

(a) Inert fillers such as asbestos fibre, viscose rayon fibre, cottonflock, etc.

(b) Reinforcing pigments and compounding ingredients such as zinc oxide,sulphur, zinc oxide and sulphur, walnut shell flour, zinc sulfide,titanium dioxide, etc.

tions, it maybe desirable to include in the composition one or moresubstances for inhibiting,

suppressing or controlling the reaction. Compounds suitable for useascorrosion inhibitors, in the composition of the invention, fall into twomain classes:

. date, magnesium. vanadate, ammonium carbam- (c) Materials which tendto mask or obviate objectionable odors.

(d) Liquids which have a swelling, softening,

plasticizing or solvent effect, or which may serve as a carrier for thecoalescing agent or other added materials. In this class are certainketones, chlorinated compounds,

etc.

(e) Syntheticresins, monomers and 'elas'tomers.

'i'g) Other additives whose use advantageously affects certainproperties of the product for a given use.

The polymeric organic polysulflde latices commercially available at thepresent time have 'a" substantial alkaline reaction, andtheir alkalinityis suiiicient to cause appreciablereaction with ate, ammoniumbicarbonate, ammonium molybdate, boric acid and ammonium borate.

2. Certain organic acids or their derivatives. Examples of this classare: salicylic acid, diammonium sebacate, diammonium salt of itaconicacid and diammonium fumarate.

Excellent results are obtained by the use of vanadium pentoxide and/orcompounds related to, derived from, or equivalent to vanadium pentoxide.1 have found vanadium pentoxide, am-

monium vanadate and ammonium metavanadate to be effective'as corrosioninhibitors. Salicylic acid also has givengood results. Other suitableinhibitors may be used, but it is important that they should not in anyway interfere with the action of the coalescing agent or have harmfuleffects uponthe latex. It is to be understood th jat theinvention isnotto be considered as restricted to the use of a corrosion inhibitor,or to the use of an aqueous Thiokol dispersionhaving an appreciablealkalinity.

. Exmnes The following examples 10f preferred sealing materials of theinvention, and manners of making or compounding the same, areillustrative and are not to be taken as limiting the scope of theinvention.

Example 1 100 parts aqueous fluid Thiokol MI (copolymer ofpolyethyleneformal polysulflde) (50% solids), 9.7 part coalescingagent-mono ethyl ammonium mono ethyl dithiocarbamate; (an dditionproduct derived from two moles of mono-ethyl amine for each mole ofcarbon disulflde) The ingredients are thoroughly mixed together and thenheated for about one hour at approximately 180 Fahrenheit, with frequentstirring or agitation. The resultant product is a grayish dispersion oflow viscosity.- Coatings of material coalesce quite satisfactorily, andare initially soft, but ultimately become tougher.

The product has good adhesion on various surfaces such as the surface ofmetals, wood, etc.

' -Ea:ample 2 100 parts Thiokol n (copolymer' of polyethyl eneformaivpolysulflde) cake:, (approxi- .mate1y,65% to 85% solids) obtained by re-The reaction is often accompanied by gas evolu- 15mm water.

tion. This may result in a discontinuous sealing coat or mass, and mayadversely aflectadhesion of the sealing material to the surface when thesealing material is applied to an alkali-sensitive surface underconditions which permit orfavor" such reaction. Where the sealingmaterial is to, be used on such surfaces andunder such 60m!!!k'movingrthe 'excessliquid from. Thiokol latex.

1; part coalescing agent-(addition product de- "rived from, two moles ofmono mole-o'f'carbon'disulfidek" i Y The .pr'ocedure'for preparing thematerial may The resultant dispersion.

benzylamine per tougher than those obtainable from the product ofExample 1.

Example 3 1 part coalescing agent, namely, mono-n-butylammonium,mono-n-butyl dithiocarbamate- (addition product derived from two molesof mono-n-butylamine for each moZe of. carbon disulflde). I

The procedure in preparing the material may be the same as in Example 1with appropriate mixing. The resultant product is a solid having aputty-like consistency. The material has excellent package stability.Applied coatings of the material coalesce very satisfactorily. haveeffective adhesion to surfaces of various natures and are initiallysoft, but ultimately become quite firm. The material may be diluted withwater to yield a fluid dispersion of any selected viscosity.

Example 4 100 parts Thiokol MF (copolymer of polyethyleneformalpolysulflde) "cake is dispersed with water and stirred thoroughly withfive parts of short fibre asbestos. The excess liquid is then removedand the resultant asbestos-flied cake is treated as set forth in Example3.

Example 5 100 parts Thiokol WD2 (polyethyleneformal polysulfide)cake(approximately 65% to 80% solids),

1.1 part coalescing agent-mono-n-butylammonium, mono-n-butyldithiocarbamate.

The procedure for preparing the material may be substantialy the same asin the case of Example 1. The resultant product is appreciably morefluid than the product of Example 1. A substantial proportion of liquidseparates and may be removed if desired, to leave a firmer and morecompact putty. The properties of the material of this example aresimilar to those of Example 3 with the following principal differences:

(a) The coatings are more translucent.

(b) There is superior coalescence in relatively thick coatings onirregular surfaces.

' (c) There is superior maintained flexibility, re

siliency and adherence throughout a greater range of temperatures. (d)Inferior solvent resistance.

Example 6 66.? parts Thiokol WD2 (polyethyleneformal polysulflde)cakeapproximately 65% to 80% solids.

33.3 parts Thiokol MF (a copolymer of polyethyleneformal polysulflde anda polyo efin polysulflde) cake-approximately 65% to 80% solids.

1.1 part coalescing agent (mono-n-butylammonium mono-n-butyldithiocarbamate) Example 7 66.7 parts Thiokol WD2 (polyethyleneformalpolysulflde cake-approximately 65% to 80% solids.

33.3 parts Thiokol MF (a copolymer of polyethyleneformal polysulflde anda polyoefln polysulflde) cake-approximately 65% to 80% solids.

1.1 part coalescing agent (mono-n-butylammonium mono-n-butyldithiocarbamate.

0.05 to 0.25 part salicylic acid.

Example 8 66.! parts Thiokol WD2 (polyethyfeneformal polysulflde)cake"approximately 65% to 0.1 to 0.5 part inhibtor-vanadium pentoxide orammonium vanadate.

The procedure in preparing the material in Exampes 6, 7 and 8 may besubstantially the same as set forth in Example 3.

The advantages to be gained by practicing the present inventiomarenumerous and will be apparent from the foregoing description. AqueousThiokol dispersions treated in accordance with the invention yieldeffective, coherent and adherent coatings and masses capable ofmaintaining full adhesion on a wide variety of materials and surfaces,and retain the desirable properties of solvent-resistance andlow-temperature flexibility generally characteristic of organicpolymeric poysulfldes. The materials are capable of forming satisfactorysealing coatings on irregular surfaces and under widely varyingconditions.

ucts and have good package stability. When the material is prepared as aputty, it has even a greater versatility. The putty-like material may bestored indefinitely in a closed container, has excellent packagestability and is in a compact form for convenient shipping and storage.The "putty may be supplied as a caulking and filleting material. andwhen so applied, yields sealing masses which coalesce thoroughly,uniformly and effectively under varying conditions. Where coatings aredesired, the thick putty-like product may be diluted with water to thedesired consistency for ready app ication as by spraying, brushing andsloshing. The coatings obtained may be of substantial thickness wheredesired, and yet will coalesce thoroughly and uniformly throu hout.

The sealing and coating materials of the invention are readilydispersible in water prior to their exposure to conditions favoringcoalescence, but have a high resistance to water after coalescence.Coatings produced by the materials are compatible with other sealingmaterials, and the usual "top coatings have good adhesion to thecoalesced coatings. The attributes of efiective resistance to a widevariety of solvents and liquids and the maintained adherence,flexibility and resiliency well suit the sealing materials of theinvention for the sealing of containers and enclosures of various kinds.

It is to be understood that the invention is not to be taken as limitedto the express procedure or examples set forth above, these detailsbeing given only by way of illustration. I do not regard such specificdetails as essential to the invention except insoar as they areexpressed by way of limitation in the appended claims, in which it is myintention to claim the invention as broadly as permissable in view ofthe prior art.

I claim:

1. The method of treating an aqueous dis- I The sealingmaterials may behandled;

distributed and marketed as one-package prod- 11 persion of apoiysulflde which is a polymer of the unit 2. The method of treating anaqueous dispersion of a polysulfide which is a polymer of the unit --(E(F-Satotwhere-(B 6- l I I I represents two carbon atoms Joined to andseparated by intervening structure, which method comprises adding to thedispersion from approximately 0.2% to approximately 10% by, weight withrespect to the solids content of the dis- 25 rated .by, interveningstructure. and a small persion of a mono-substituted member of the groupconsisting of alkyi, arylalkyl, alkeno and cyclo-alkyl monoamine salt ofa member or the group consisting of alkyl, arylalkyl, alkeno andcylo-alkyl substituted dithiocarbamic acids, and

the ammonium salt of dithiocarbamic acid.

3. The method of treating an aqueous dispersion oi a polysuiflde theunit represents two carbon atoms joined to and separated by interveningstructure, which method comprises adding to the dispersion a, smallamount of mono-normal-butylammonium mononormal-butyl dithiocarbamate.

4. The method of treating an aqueous dis-'- persion oi a polysulfldewhich is a polymer of represents two carbon atoms joined to andseparated by intervening structure, which method.

comprises adding to the dispersion a small amount of mono-allyiammoniummono-ally] dithiocarbamate.

5. A sealing composition comprising an aqueous dispersion of apolysulflde which is the polymer or the unit -d JSito6where d- I I I Irepresents two carbon atoms. joined to and separated by interveningstructure, and a small o-sitoowhere-d A I I I I represents two carbonatoms joined to and separated by intervening structure,- and fromapproxmately 0.2% to approximately 10% by'weight which is a polymer ofwith respect to the solids content of said dis- 5 group consisting ofvalkyl, aralkyl, alkeno and cyclo-alkyl substituted dithiocarbamicacids, and the ammonium salt of dithiocarbamic acid.

7. A sealing composition comprising an aqueous dispersion oi. apolysulflde which is the poly- I I o mer oi the unit represents twocarbon atoms joined to and separated by intervening structure, and asmall 15 amount of a coalescing agent comprising as its principal activeingredient mono-normal-butyiammonium mono-normal butyl dithiocarbamate.

8. A sealing composition comprising an aqueous dispersion of apolysulfide which is the polymer oi the unit 7 0-1:, S,to0where (:J-represents two carbon atoms Joined to and sepaamount of a coalescingagent comprising as its principal active ingredient mono-allylammoniummono-allyl' dithiocarbamate.

9. A sealing composition comprising an aque- 80 bus dispersion of a.polysulflde which is the polymer or-the'unit I s x-antennae( t I i- 3represents two carbon atoms joined to and separated by interveningstructure, and from approximateiy 0.2% to approximately 10.0% by weightwith respect to the solids content of. said dispersion of a coalescingagent containing as its prin- 49 cipal active ingredient mono-normalbutylammonium mono-normal butyl dithiocarbamate.

10. A sealing composition comprising an aqueous dispersion of apolysulfide which is the polya mer of the unit' represents two carbonatoms joined to and sepa- I 5 rated by intervening structure, and fromapproximately 0.2% to approximately 10.0% by weight with respect to thesolids content of said dispersion of a coalescing agent containing asits principal active ingredient mono-allylammonium mono- 55 allyldithiocarbamate.

11. A sealing composition comprising an aqueous dispersion oi. apolysuliide which is the poly- I mer .of the unit represents two carbonatoms joined to and separated by intervening structure, a small amountof a mono substituted member of the group con- 05 sisting of alkyl,arylalkyl, alkeno, and cyclo-alkyl monoamine salt of a member of thegroup consisting of alkyl, arylalkyi, alkeno and cyclo-alkyl substituteddithiocarbamic acids. and the ammonium salt of dithiocarbamic acid, anda small- 70 amount of an oxygenated vanadium compound in which vanadiumis inone of its higher states of oxidation to serve as an inhibitor forpreventing alkaline attackof the sealing composition on alkali-sensitivematerials.

.76. 12. Asealing composition comprising an aqueous dispersion of apolysulfide which is the polymer of the unit.

represents two carbon atoms joined to and separated by interveningstructure, a small amount of a mono substituted member of the groupconsistin of alkyl, arylalkyl, alkeno, and cyclo-alkyl monoamine salt ofa member of the group consisting of alkyl, arylalkyl, alkeno andcycio-alkyl substituted dithiocarbamic acids, and the ammonium salt ofdithiocarbamic acid, and a. minor proportion of vanadium pentoxideserving as an inhibitor for preventing alkaline attack of the sealingcomposition on alkali-sensitive materials.

13. A sealing composition comprising an aqueous dispersion of apolysulflde which is the polymer of the unit ous dispersion of apolysulfide which is a polymer of the unit -Jl (}S to6whero (I3- I l I Irepresents two carbon atoms Joined to and separated by interveningstructure, from approximately 0.2% to approximately 10% by weight withrespect to the solids content of said dispersion of a. coalescing agentcomprising as its principal active ingredient a mono-substituted memberor the group consisting of alkyl, arylallryl.

alkeno, and cyclo-alkyl monoamine salt of a mem- 14 her of the groupconsisting of alkyl, arylalkyl, alkeno and cycio-alkyl substituteddithiocarbamic acids and the ammonium salt of dithiocarbamic acid, and asmall amount of vanadium pentoxide serving as an inhibitor forpreventing alkaline attack of the sealing composition onalkali-sensitive materials.

15. A sealing composition of heavy consistency adapted to be applied assupplied and adapted to be thinned with water comprising approximately100 parts by weight of an aqueous dispersion of a polysulfide which is apolymer of the unit represents two carbon atoms joined to and separatedby intervening structure, said dispersion containing from approximately65% to approximately 80% solids; and from approximately 0.2% toapproximately 10.0% by weight, with respect to the solids content ofsaid dispersion, of a coalescing agent containing as its principalactive ingredient a mono-substituted member of the group consisting ofalkyl, arylalkyl, alkeno, and cyclo-alkyl monoamine salt of a member ofthe group consisting of alkyl, arylalkyl, alkeno and cyclo-alkylsubstituted dithiocarbamic acids, and the ammonium salt ofdithiocarbamic acid.

FREDERIC M. CARASSO.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,140,063 Talalay Dec. 13, 19382,186,714 Youker Jan. 9, 1940 2,206,642 Patrick July 2, 1940 2,261,439Kelly Nov. 4. 1941 2,379,464 Thies July 3, 1945 FOREIGN PATENTS NumberCountry Date 422,826 Great Britain Jan. 18, 1935 499,747 Great BritainJan. 24, 1939

